Possessing excellent English grammatical knowledge makes a pre-service teacher facilitate classroom learning effectively; however, some hesitate to use the language due to one’s level of proficiency. This situation becomes upsetting as these students are soon to practice their profession, thus, it demands examination on students exposure to English language stimuli vis-à-vis with grammatical knowledge. Employing the descriptive – correlation design, the study aimed to investigate the influence of English language exposure to the grammatical knowledge of 65 pre-service Education students who were chosen through complete enumeration technique. More particularly, it sought to determine extent of English language exposure at home, with social group, in school, on social media and their level of grammatical knowledge in terms of phonology, vocabulary, and syntax. An adapted and validated-researcher made questionnaire determined students’ extent of language exposure and their level of grammatical knowledge. Findings revealed that despite less English language exposure, the pre-service teachers’ level of grammatical knowledge was high. Furthermore, Pearson r and the coefficient of determination analysis divulged that the English language exposure had a significant influence to the grammatical knowledge of the pre-service teachers.